Instant Mock Testing with PowerMock

Discover unit testing using PowerMock

Overview

• Learn something new in an Instant! A short, fast, focused guide delivering immediate results
• Understand how to test unit code using PowerMock, through hands-on-examples
• Learn how to avoid unwanted behaviour of code using PowerMock for testing
• Explore the features of PowerMock through the selection of clear, practical, step-by-step recipes

In Detail

Writing good unit tests can be hard in situations where we have to deal with static, final, or private methods. Sometimes, even a good design is sacrificed for the sake of testability. A mocking framework’ s ability to create mocks for almost any scenario enables us to focus on accurately programming for a business environment.

Starting with a basic example of how to create a mock and verify a method invocation Instant Testing with PowerMock then demonstrates various features of PowerMock using clear, practical, step-by-step recipes. By the end of this book, you will be able to write unit tests for almost any scenario and suppress unwanted behaviour to effectively unit test your code.

Moving on from the basics, you will learn to write unit tests for static, final, and private methods, and write flexible unit tests using argument matchers. Following on from this, you will also learn how to mock a few methods of a class, and invoke real implementation of others using partial mocks or spies. This book will teach you the tricks of the trade that will enable you to write good unit tests for a wide range of scenarios.

What you will learn from this book

• Learn how to mock final classes and methods
• Use argument matchers to write flexible tests
• Invoke private methods and verify the internal state of a class
• Suppress unwanted constructors, methods, fields, and static initializers
• Set up mocking code once and use Mock Policies to avoid writing repetitive code

Approach

Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. A concise guide full of step-by-step recipes, to teach you how you can use PowerMock to unit test code.

Who this book is written for

If you are a beginner who would like to learn how to use PowerMock, this is the perfect guide for you! As the book comprehensively covers both basic and advanced concepts, this guide is also suitable for those of you who have an intermediate knowledge of PowerMock.

Table of Contents

1. Instant Mock Testing with PowerMock
2. Saying Hello World! (Simple)
3. Getting and installing PowerMock (Simple)
4. Mocking static methods (Simple)
5. Verifying method invocation (Simple)
6. Mocking final classes or methods (Simple)
7. Mocking constructors (Medium)
8. Understanding argument matchers (Medium)
9. Understanding the Answer interface (Advanced)
10. Partial mocking with spies (Advanced)
11. Mocking private methods (Medium)
12. Breaking the encapsulation (Advanced)
13. Suppressing unwanted behavior (Advanced)